using Microsoft.AspNetCore.Mvc;
using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.Logging.Abstractions;
using TaskTracker.Api.Controllers;
using TaskTracker.Core.DTOs;
using TaskTracker.Core.Entities;
using TaskTracker.Infrastructure.Data;
using TaskTracker.Infrastructure.Repositories;
using Xunit;

namespace TaskTracker.Tests;

public class TasksControllerDeadlineTests
{
    [Fact]
    public async Task Create_copies_due_at_including_offset_to_created_task()
    {
        await using var db = CreateDbContext();
        var controller = CreateController(db);
        var dueAt = DateTimeOffset.Parse("2026-08-14T11:00:00-04:00");

        var result = await controller.Create(new CreateTaskRequest { Title = "deadline", DueAt = dueAt });

        var created = Assert.IsType<CreatedAtActionResult>(result);
        var response = Assert.IsType<ApiResponse<WorkTask>>(created.Value);
        Assert.Equal(dueAt, response.Data!.DueAt);
    }

    [Fact]
    public async Task Update_changes_due_at_when_value_is_supplied()
    {
        await using var db = CreateDbContext();
        var task = await AddTaskAsync(db, DateTimeOffset.Parse("2026-08-14T11:00:00-04:00"));
        var controller = CreateController(db);
        var dueAt = DateTimeOffset.Parse("2026-08-15T09:30:00+02:00");

        var result = await controller.Update(task.Id, new UpdateTaskRequest { DueAt = dueAt });

        var ok = Assert.IsType<OkObjectResult>(result);
        var response = Assert.IsType<ApiResponse<WorkTask>>(ok.Value);
        Assert.Equal(dueAt, response.Data!.DueAt);
    }

    [Fact]
    public async Task Update_clears_due_at_only_when_clear_due_at_is_true()
    {
        await using var db = CreateDbContext();
        var task = await AddTaskAsync(db, DateTimeOffset.Parse("2026-08-14T11:00:00-04:00"));
        var controller = CreateController(db);

        var result = await controller.Update(task.Id, new UpdateTaskRequest { ClearDueAt = true });

        var ok = Assert.IsType<OkObjectResult>(result);
        var response = Assert.IsType<ApiResponse<WorkTask>>(ok.Value);
        Assert.Null(response.Data!.DueAt);
    }

    [Fact]
    public async Task Update_with_omitted_due_at_preserves_existing_due_at()
    {
        await using var db = CreateDbContext();
        var dueAt = DateTimeOffset.Parse("2026-08-14T11:00:00-04:00");
        var task = await AddTaskAsync(db, dueAt);
        var controller = CreateController(db);

        var result = await controller.Update(task.Id, new UpdateTaskRequest { Title = "renamed" });

        var ok = Assert.IsType<OkObjectResult>(result);
        var response = Assert.IsType<ApiResponse<WorkTask>>(ok.Value);
        Assert.Equal(dueAt, response.Data!.DueAt);
    }

    private static TaskTrackerDbContext CreateDbContext()
    {
        var options = new DbContextOptionsBuilder<TaskTrackerDbContext>()
            .UseInMemoryDatabase(Guid.NewGuid().ToString())
            .Options;
        return new TaskTrackerDbContext(options);
    }

    private static TasksController CreateController(TaskTrackerDbContext db) =>
        new(new TaskRepository(db), NullLogger<TasksController>.Instance);

    private static async Task<WorkTask> AddTaskAsync(TaskTrackerDbContext db, DateTimeOffset dueAt)
    {
        var task = new WorkTask { Title = "existing", DueAt = dueAt };
        db.Tasks.Add(task);
        await db.SaveChangesAsync();
        return task;
    }
}